The disclosure relates to an OLED display panel and its fabricating method, and an OLED display apparatus.
Organic Light-Emitting Diode (OLED) display panel, also known as Organic electroluminescent display panel, due to its high brightness, low power consumption, high contrast, fast response, is widely used by academia and industry, and is considered to be the next generation of new display technology which can replace LCD.
An OLED display panel includes a front substrate, a rear substrate, and an anode layer, a light-emitting layer and a cathode layer disposed sequentially between the front substrate and the rear substrate, wherein the light-emitting layer includes red sub-pixel (R), green sub-pixel (G) and blue sub-pixel (B), and the voltage between the anode layer and the cathode layer corresponding to R, G and B is controlled according to a formulation, so that R, G and B emit red light, green light and blue light with respective brightness (three primary colors), to form a desired color.
In practice, for the fabrication of a light-emitting layer of the above OLED display panel, it requires the use of Fine Metal Mask (hereinafter referred to FMM MASK) evaporation process three times to evaporate R, G and B respectively. Further, in order to ensure the resolution, the aperture ratio of FMM MASK at each evaporation process is generally limited to less than 300 ppi, or even, in order to further improve the resolution, the aperture ratio of FMM MASK should be further reduced, the so-called aperture ratio of FMM MASK referring to, for each sub-pixel, the ratio of area through which light can pass of the MASK (i.e., area of the aperture) to the total area.
However, it is found in practical applications that the low aperture ratio of FMM MASK easily leads to blocked FMM MASK aperture in the evaporation process, and results in line defects and color mixing on the OLED display panel with poor quality.